diff --git a/Source/BugsnagKSCrashSysInfoParser.m b/Source/BugsnagKSCrashSysInfoParser.m
index 59a5a5ea0..354f8a784 100644
--- a/Source/BugsnagKSCrashSysInfoParser.m
+++ b/Source/BugsnagKSCrashSysInfoParser.m
@@ -118,7 +118,13 @@
     BSGDictSetSafeObject(deviceState, report[@"machine"], @"model");
     BSGDictSetSafeObject(deviceState, report[@"system_name"], @"osName");
     BSGDictSetSafeObject(deviceState, report[@"system_version"], @"osVersion");
-    BSGDictSetSafeObject(deviceState, report[@"os_version"], @"osBuild");
+
+    NSString *osVersion = report[@"os_version"];
+
+    if (osVersion != nil) {
+        BSGDictSetSafeObject(deviceState, @{@"osBuild": osVersion}, @"runtimeVersions");
+    }
+
     BSGDictSetSafeObject(deviceState, @(PLATFORM_WORD_SIZE), @"wordSize");
     BSGDictSetSafeObject(deviceState, @"Apple", @"manufacturer");
     BSGDictSetSafeObject(deviceState, report[@"jailbroken"], @"jailbroken");
diff --git a/Tests/BugsnagSinkTests.m b/Tests/BugsnagSinkTests.m
index b783f0c8b..bddbc6e13 100644
--- a/Tests/BugsnagSinkTests.m
+++ b/Tests/BugsnagSinkTests.m
@@ -270,7 +270,7 @@ - (void)testEventDevice {
     XCTAssertEqualObjects(device[@"modelNumber"], @"MacBookPro11,3");
     XCTAssertEqualObjects(device[@"osName"], @"iPhone OS");
     XCTAssertEqualObjects(device[@"osVersion"], @"8.1");
-    XCTAssertEqualObjects(device[@"osBuild"], @"14B25");
+    XCTAssertEqualObjects(device[@"runtimeVersions"][@"osBuild"], @"14B25");
     XCTAssertEqualObjects(device[@"totalMemory"], @15065522176);
     XCTAssertNotNil(device[@"freeDisk"]);
     XCTAssertEqualObjects(device[@"timezone"], @"PST");